The shimano hg54 10 speed hgx chain is optimised for shimano 10 speed hg x mtb drivetrains only and has a grey corrosion resistant finish on both inner and outer plates it uses a directional design with specifically shaped inner and outer plates to optimise shifting over the chainset and cassette the inner plate has been developed for better contact with gears providing smoother shifting under high load giving efficient pedalling increased rigidity and near silent running and the outer plate